This invention relates to electronic tuning type recievers, and more particularly to a muting circuit in such a receiver in which noise caused by station movement in selecting a station is eliminated.
Recently, thanks to the rapid development of electronics, a receiver in which an electronic preset station selection operation can be carried out has been proposed. This preset type receiver is so designed that a memory is addressed by the outputs of a band selecting switch and a channel selecting switch, the signals of preset band and channel are read into the address in the memory from an up-down counter during-manual setting operation, and the output of the up-down counter is simultaneously converted into an analog signal which is supplied to a varicap diode forming a tuning circuit, whereby the radio wave of the desired band and channel being preset can be received. In this case, the channel selecting switch is made of, for instance, a non-lock type switch, while the band selecting switch is made of, for instance, a rotary switch. Thereafter, whenever a channel selecting signal outputted by the channel selecting switch and a band selecting signal outputted by the band selecting switch are detected, the output of the memory is inputted into the up-down counter to control the receiver.
However, when the preset station selection is carried out by operating the band selecting switch and the channel selecting switch with the electronic tuning type receiver organized as described above, the receiver tuning is adjusted to stabilize at an aimed station. Therefore, the above-described receiver is disadvantageous in that noise is produced during this station adjustment.